Gas discharge tube having a number of juxtaposed matrix groups for displaying characters

ABSTRACT

A multiple matrix tube in which the planes of cathodes and anodes extend at right angles to the wide surfaces of the connection strips connected to said electrodes, said strips being placed against each other with the interposition of insulating strips.

1 May Li973 United States Patent Hendriks R GT mA M DG HEN I. PA T P mm R F OE FT W SC IEPA D UR SMOA AURH GNGC m X 5 9 0 l 3 l 3 3,041,491 6/1962 Cistola........ 3,588

[75] Inventor: Adrianus Antonius Maria Hendriks,

Emmasingel, Eindhoven, Netherlands ,571 6/1971 Uemura et al..... ....3l3/109.5

383 Tagawa............................

[ Assignee: Philips Corporation, New Prim? Emmmer-palmr Demeo Y k N Y Attorney-Frank R. Trifarl 22 Filed:

[57] ABSTRACT A multiple matrix tube in which the planes of Oct. 6, 1971 [211 Appl. No.: 186,913

cathodes and anodes extend at right angles to the wide surfaces of the connection strips connected to said electrodes, said strips being placed against each other with the interposition of insulating strips.

Foreign Application Priority Data Oct. 17,1970 Netherlands ........................7015261 5 e r u g .I F g .m W a r U 5 s m a l C 4 16 1 3m B 2 3 7 mu ,02 was 2 u .9 W 0 l 1 3 N 5 In 9 mm 0 "n 1 t I n" 3 n n N "u mmhu "c r a "e "s l l rm 5min UIIF,. 1.11 218 555 [.121

PATENTED MAY 1 I973 SHEET 2 OF 3 IN VENTOR. ADRIANUS ANTONIUS MARIA HENDRIKS AG ENT PATENT ED W 1 I975 SHEET 3 UF 3 INVEJVIOR. ADRIANUS ANTONIUS MARIA HENDRIKS GAS DISCHARGE TUBE HAVING A NUMBER OF J UXTAPOSED MATRIX GROUPS FOR DISPLAYING CHARACTERS The invention relates to a gas discharge tube having a number of juxtaposed matrix groups for displaying characters, in particular digits, which tube comprises a number of cold cathodes which are divided into juxtaposed matrix groups, each group having an associated anode, the corresponding cathodes of all the groups being connected to a continuous connection strip or forming part of it, said continuous connection strips being stacked one on the other with the interposition of insulating material.

Such a tube is known from German Offenlegungschrift 1,948,321, Priority date Sept. 25, 1968 and Oct. 7 1968, Japan, published on Apr. 23, 1970, in the name of Matsuschita Electronic Corp.

Although the above-described construction of such a multiple matrix tube has many advantages, the drawback exists, however, that the cathodes after stacking are not located in one plane as a result ofthe thickness of the insulating material present between the strips. Therefore the various cathodes of a matrix group must be bent locally over different heights so as to bring all of the said cathodes in one flat plane. This is complicated. In addition, the height of the matrix groups on the upper and lower side is increased by the width of the strips so that the height of the characters must be smaller with a given cross-section of the envelope.

The said drawbacks can be avoided for the greater part while maintaining the advantages in a gas discharge tube for displaying a number of juxtaposed characters, which tube comprises a number of cold cathodes which are divided into juxtaposed matrix groups each having an associated anode, the corresponding cathodes of all the groups being connected to a connection strip or forming part of it, said connection strips being stacked one on the other with the interposition of insulating material, the cathodes of all the matrix groups being present in a flat plane and all the anodes being present in a second plane which is parallel to the plane of the cathodes, if, according to the invention, the wide surface of eachof the continuous strips encloses an angle of substantially 90 with the electrode planes.

In the knowntubes the anodes were provided with separate contact pins or they were connected to contact pins sealed in the ends of the tube with comparatively long conductors in the form of a wire. This necessitated a large number of sealed contact pins divided over the length of the tube of a large number of long conductors to contactpins at the ends of the tube, which extend immediately beside each other and which have to be insulated from each other. As a result of this the construction of the known tubes became complicated and hence expensive.

Ina tube according to the invention, each anode is connected to a separate continuous strip and all the anode strips are placed against each other with the interposition of an insulating material. In this case also the wide surface of the continuous strips extends preferably at right angles to the electrode planes.

For most of the electrodes, the thickness and the number of insulating layers and strips placed against each other now no longer any influence on the location of the plane in which the electrodes connected to the strips are located, so that substantially all the cathodes can be located in one plane without it being necessary for them to be bent locally. The strips which serve as current supply conductors for the anodes can also be laid simply against each other with the interposition of insulating strips without influencing the dimensions of the envelope of the tube.

The invention will now be described with reference tothe accompanying drawing, in which:

FIG..1 is a perspective view of a matrix tube according to the invention,

FIG. 2 shows the construction of the cathode system,

F IG. 3 shows the construction of the anode system,

FIG. 4 is a perspective side elevation from the left and FIG. 5 is a cross-sectional view through the tube.

Reference numeral 1 in FIG. 1 denotes the envelope of a matrix gas discharge tube in which in this case, for example, nine juxtaposed characters, for example a number, can be displayed. In FIG. 1 the number 713458.026 is displayed. The envelope 1 is closed at either end by means of caps 2 and 3 in which contact pins 4 are sealed. The pins in the cap 2 serve, for example, for the strips with anodes, those in the cap 3 for the cathodes and screenings. Each matrix group consists,

for example, of an anode and eight cathodes. Seven cathodes of a group serve to display digits, one cathode serves as a decimal point.

The cathode system of the tube shown in FIG. 1 is constructed from the components as they are shown in FIG. 2.

The continuous metal connection strips 6 of the cathode strips enclose an angle of substantially 90 with the cathodes 7, 8 and 9 connected thereto. The strips 6 are clamped between insulating strips 5 against the sides of a U-shaped metal plate 10. Screens 11 are arranged between the matrix groups. The upper side of the U-shaped plate is closed by a mica plate 12. The cathodes 7 and 8 of the upper -and lower side of the matrix can project directly into thespace of the U- shaped strip '10 from their connection strips 6 and are visible through the apertures of the insulating plate12. The cathode 9 placed centrally over the matrix group extends over the plate 12 on the upperside and is bent at right angles and bent locally over the thickness of the plate 12 as a result of which the operative part 9 lies in the same plane as the cathodes 7 and 8. The non-operative parts of the cathodes 9 are covered by the insulating plate 13. The whole system is surrounded by the assembly of the metal components denoted by 15 which are arranged in the housing 16. The housing 16 is welded with the side walls to the lugs 14 of the U- shaped plate 10 as a result of which the stacked continuous strips 6 and the insulating strips 5 are closed between the upper sides of the lugs 14, the side walls of bent laterally through 90 and then bent back through 180 so that the anodes l7 become located substantially flat on the strip 20. The stack of the continuous strips 18 and the insulating strips 19 is arranged in the available space in the bottom of the tube. This is possible since the wide surface of each strip 18 extends at right angles to the plane of the anodes 17.

The construction of the whole system is shown in FIG. 4 which is an elevation of the electrode system on the side where the cathode strips are conducted to the contact pins 4. The strips 18 and 19 of the anode system terminate against a mica centering member 21. An upright surface 16A of the housing 16 engages the mica member 21 and is connected thereto by bent lugs 22. The U-shaped plate is connected to the mica member 21 by means oflugs 23.

FIG. 5 shows a sectional view of the tube from which it may be seen that the housing 16 on the other side of the system where the anodes are conducted to the contact pins is connected with the upright part 16B to a mica centering member 24. This centering member 24 comprises an aperture through which the strips 18, 19 extend The angular strips 25 (see also FIG. 3), the wall of the housing 16 and the lugs 14 are connected together by spot-welding.

Owing to the embodiment according to the invention in which the connection strips extend at right angles to the electrode planes, a multiple matrix tube which is easy to assemble is obtained in which the occupation of the cross-section of the tube is as favorable as possible. Besides of eight cathodes (including the decimal point) the matrix group may also consist, for example, of 10 or more cathodes, as is known per se. A larger number of electrodes involves substantially no greater difficulties as regards the location thereof in one plane, since the thickness of the stack of strips in principle has no influence on the plane of the electrodes connected thereto.

What is claimed is:

1. A gaseous discharge display tube comprising an elongated sealed envelope containing an ionizable gas, at least a portion of said envelope being transparent, a plurality of cathodes divided into juxtaposed matrix groups, an anode associated with each of said groups of cathodes, a plurality of continuous connection strips each connected to corresponding cathodes of all of said groups, said connection strips being arranged in a stack, strips of insulating material separating adjacent connection strips in said stack, all of said cathodes being in one plane, all of said anodes being in a second plane extending parallel to the plane of the cathodes, the wide surfaces of the connection strips forming an angle of substantially with the planes of the anodes and cathodes.

2. A gas discharge tube as claimed in claim 1, wherein each anode is connected to a separate continuous strip and all said strips are placed against each other with the interposition of an insulating material.

gas discharge tube as claimed in claim 2,

wherein each anode forms one assembly with the associated continuous strip and, viewed in the longitudinal direction of the strip, is first bent laterally through 90 in one direction and then through in the opposite direction.

4. A gas discharge tube as claimed in claim 1, wherein the connection strips of the cathodes are connected to contact members at one end of the envelope, the connection strips of the anodes being connected to contact members at the other end of the envelope. 

1. A gaseous discharge display tube comprising an elongated sealed envelope containing an ionizable gas, at least a portion of said envelope being transparent, a plurality of cathodes divided into juxtaposed matrix groups, an anode associated with each of said groups of cathodes, a plurality of continuous connection strips each connected to corresponding cathodes of all of said groups, said connection strips being arranged in a stack, strips of insulating material separating adjacent connection strips in said stack, all of said cathodes being in one plane, all of said anodes being in a second plane extending parallel to the plane of the cathodes, the wide surfaces of the connection strips forming an angle of substantially 90* with the planes of the anodes and cathodes.
 2. A gas discharge tube as claimed in claim 1, wherein each anode is connected to a separate continuous strip and all said strips are placed against each other with the interposition of an insulating material.
 3. A gas discharge tube as claimed in claim 2, wherein each anode forms one assembly with the associated continuous strip and, viewed in the longitudinal direction of the strip, is first bent laterally through 90* in one direction and then through 180* in the opposite direction.
 4. A gas discharge tube as claimed in claim 1, wherein the connection strips of the cathodes are connected to contact members at one end of the envelope, the connection strips of the anodes being connected to contact members at the other end of the envelope. 